Forget casual Fridays. In many workplaces, it's casual everyday as corporate dress codes have gone the way of fedoras and white gloves. Office workers, from executives to receptionists, now wear pretty much what they want, sometimes baring more cleavage, tattoos and body fat than co-workers care to see.

The sartorial style pioneered by the T-shirt-and-jeans-wearing technology moguls of Silicon Valley more than a decade ago has spread even to law offices, accounting firms and corporate headquarters — bastions of tradition that had kept generations of Brooks Brothers salesmen busy teaching customers how to fold silk pocket squares.

Polo shirts, sweater sets and tailored slacks — what many companies consider "business casual" — have given way to halter tops, rubber flip-flops, T-shirts and jeans. The trend has even sparked a mini-backlash among professionals opting for a more buttoned-down look. "Wearing a tie used to be a sign of conformity. But dressing down is now conformity and dressing up is rebellious," said Robert Stephens, who founded the Geek Squad, Best Buy Co.'s computer repair service.

Squad members sport short-sleeve white shirts and black ties.

Credit younger workers, who bring a who-cares-what-I-wear attitude to their cubicles, for the casual-everyday trend. The hip-hugging jeans and silk-screened tees they favor have caught on with aging baby boomers, many of whom started their careers with a closet full of pinstriped "power" suits. Many women believe they no longer need to look suited-up like men to be taken seriously in the office.

Today's casual dress also reflects the needs of parents who want to be comfortable as they race from staff meetings to their kids' soccer practice. Employers who once took a hard line on suits and pantyhose realized they risked losing valued staff members unless they lightened up. Many see their relaxed dress codes as a potential recruiting tool. "It really helps us, specifically with Gen X and Y workers," said Miriam Wardak, senior vice president for ICF International, a Virginia-based consulting firm, adding that some younger workers have told her they would not consider a potential employer if they had to wear a suit and tie.

But today's lax dress codes are raising tough questions for managers about what's acceptably casual and what's too sloppy, offensive or revealing. Most companies have dress codes, whether formal or informal. "Companies want neat and clean, a notch above what you might wear at home," said John Challenger, who heads outplacement firm Challenger, Gray & Christmas Inc. But some workplaces seem to have abandoned hope of even that.

Well, maybe image isn't everything, despite Andre Agassi's claims to the contrary (in Canon Cameras' mid-1990s advertising campaign). But I'm old-fashioned when it comes to professional wear, and as one of the few who lecture in a business suit in my department, I'd also qualify as something of a rebel, as discussed in the article. No matter. Professional presentation is an essential element of business (or academic) success, and I pride myself on setting a standard of personal style and decorum in the classroom. If a suit and tie is de rigueur for the job interview, it should be no less important in the actual workplace. I remember as a kid my Dad always being impeccably dressed. When we'd travel to big cities, Dad would always visit the finest men's stores in town, for example, Cable Car Clothiers in San Francisco. To this day I wear traditional mens suits, dark wool and single-breasted, and cap-toe lace-ups. I like Brooks Brothers, though I usually settle for something comparable but less pricey. I keep promising myself I'll splurge one of these holiday seasons on a couple of Brooks Brothers suits, but there's always something more pressing around holiday time.